\documentclass{article}
\usepackage{amssymb,amsmath,amscd,concmath}
\pagestyle{empty}
\begin{document}
\begin{equation*}
F(x;\mu,\sigma)
=
\frac{1}{\sigma\sqrt{2\pi}}
\int_{-\infty}^infty
 \exp
  -\frac{(x - \mu)^2}{2\sigma^2}
\, dx
.
\end{equation*}
\end{document}
